var VehicleManager = function(){
	this.interact = function(tpf,entities){
		for(var i=0;i<entities.length;i++){
		vehicleComponent = entities[i].vehicleComponent;
		
		vehicleComponent.steering_force = vehicleComponent.steering_direction.truncate(vehicleComponent.max_force);
		vehicleComponent.acceleration = vehicleComponent.steering_force.x(1/vehicleComponent.mass); // steering_force/mass
		vehicleComponent.velocity = vehicleComponent.velocity.add(vehicleComponent.acceleration.x(tpf)).truncate(vehicleComponent.max_speed);
		entities[i].spatialComponent.position = entities[i].spatialComponent.position.add(vehicleComponent.velocity.x(tpf));
		
		vehicleComponent.steering_direction = new Vector.Zero(2);
		}
	}
}